1. Field of the Invention
The present invention relates to a drying apparatus for processing a workpiece, such as a semiconductor wafer, a liquid crystal panel or the like, by a drying process, and a substrate processing system (a substrate processing apparatus) including the drying apparatus. The present invention relates also to a drying method of drying a workpiece, such as a semiconductor wafer, a liquid crystal panel or the like, by a drying process and a substrate processing method. The present invention relates also to a storage medium (a program recording medium) storing a program specifying a drying method of processing a workpiece, such as a semiconductor wafer, a liquid crystal panel or the like, by a drying process.
2. Description of the Related Art
A manufacturing process for manufacturing a semiconductor device, a flat display or the like includes a drying step of processing a workpiece processed by a cleaning process, such as a semiconductor wafer, a liquid crystal panel or the like, by a drying process. A known drying apparatus used in the drying step is disclosed in, for example, the Japanese Patent Laid-Open Publication No. 11-186212. This known drying apparatus supplies a dry vapor for drying a workpiece, such as IPA gas (isopropyl alcohol gas), together with a carrier gas, such as nitrogen gas, into a processing tank. The dry vapor comes into contact with the surface of the workpiece in the processing tank to dry the workpiece.
The known drying apparatus has a drying tank and a dry vapor supply nozzle placed on the drying tank. The drying gas supply nozzle is connected through a mixing device to a dry vapor source and a carrier gas source. This drying apparatus supplies the dry vapor and the carrier gas simultaneously and continuously through the drying gas supply nozzle into the processing tank. The dry vapor comes into contact with the surface of the workpiece in the processing tank so as to dry the workpiece.
Since this drying apparatus supplies the dry vapor and the carrier gas simultaneously and continuously into the processing tank, the high-temperature, high-concentration, gaseous dry vapor can be continuously blown against the surface of the workpiece and it is possible that the dry vapor condenses on the surface of the workpiece if the high-temperature, high-concentration dry vapor is blown continuously against the surface of the workpiece. The surface of the workpiece may possibly be contaminated if the dry vapor condenses on the surface of the workpiece.
When a wafer, in particular, is processed as a workpiece, contaminants, such as particles and metals or organic impurities, adhered to an unusable peripheral area of the surface of the wafer when the wafer is chucked for carrying may flow together with the condensate of the dry vapor from the unusable peripheral area to an usable inner area, in which devices are formed, of the surface of the wafer and the usable inner area may be contaminated with the contaminants.